import java.util.*;

public class _10_ExtractAllUniqueWords {

	public static void main(String[] args) {
		
		Scanner in = new Scanner(System.in);
		String input = in.nextLine();
		in.close();
		
		String[] splittedText = input.split("\\W");
		List<String> list = new ArrayList<String>(Arrays.asList(splittedText));
		//list.removeAll(Arrays.asList("", null));
		list.removeAll(Collections.singleton(""));
		
		SortedSet<String> set = new TreeSet<String>();
		
		for (int i = 0; i < list.size(); i++) {
			
			set.add(list.get(i).toLowerCase());
		}
		
		List<String> sortedList = new ArrayList<String>(set);
		
		for (int i = 0; i < sortedList.size(); i++) {
			
			System.out.print(sortedList.get(i) + " ");
		}
	}
}